1. Technical Field
The present disclosure relates generally to styrenic polymer compositions and more specifically to improved methods of making styrenic polymer compositions and using same.
2. Background
Elastomer-reinforced polymers of monovinylidene aromatic compounds such as styrene, alpha-methylstyrene, and ring-substituted styrene have found widespread commercial use. For example, elastomer-reinforced styrene polymers having discrete elastomer particles and/or cross-linked elastomer dispersed throughout the styrene polymer matrix can be useful for a range of applications including food packaging, office supplies, point-of-purchase signs and displays, housewares and consumer goods, building insulation, and cosmetics packaging. Such elastomer-reinforced polymers are commonly referred to as impact modified or high impact polystyrene (HIPS) while a styrene homopolymer may be referred to as general-purpose polystyrene (GPPS).
During the production of styrenic polymer compositions, antioxidants, such as a phenol, a phosphite, or combinations thereof are generally added to the production process to stabilize the polystyrene. One challenge to the use of antioxidants in the production process is that the addition of antioxidants downstream in the production process may negatively impact downstream processing and/or affect the utility of the styrenic polymer compositions. Additionally, initiators are added to produce radical species that promote polymerization reactions. One challenge to the use of initiators in the production of styrenic polymer compositions is that the compounds may contribute to the degradation of the antioxidant thus decreasing the efficiency of the initiator when used in a polymerization reaction. Thus, it would be desirable to develop improved methodologies for preparing styrenic polymer compositions.